Relativity User Group on Basic Searching with Regular Expressions

Relativity User Group on Basic Searching with Regular Expressions

Tonight I attended a Relativity User Group on Basic Searching with Regular Expressions at the offices of DLA Piper in Manhattan.

The instructor Bill Bailey explained how to run RegEx searches in dtSearch He covered searching for digits; quantifiers; variable length quantifiers; and character sets. Bill noted that RegEx can be used with STRs and other search methods in Relativity. RegEx searches using dtSearch in Relativity must be placed in straight quotation marks and be preceded by two number signs. He cautioned us to use a plain text editor and not MS Word to structure RegEx searches. \d can be used to search for a single digit. {n,m} searches for a character that precedes it repeated between n and m times. It is not advisable to use upper case in RegEx, and you can’t search for spaces in dtSearch. The maximum word size is 32 characters. In order for special characters to be searchable a default setting must be changed in dtSearch.

\d\d searches can be strung together to search for multiple digits. A member of the group pointed out that he’d noticed limitations on RegEx searches in Relativity that were not present in dtSearch desktop. He wondered if a search for /d/d/d/d would tax the system more than {4}. The group took brief exams on how to run RegEx searches.

A search for a part number starting with b followed by 3 to 5 digits where the second digit is a 2 should be entered this way: “##b\d2\d{1,3}”

We can use square brackets to create a set of characters the search should be limited to. So for example: [01]{6} ... would limit a search to any six digit binary number. If you want to search for a word containing at least one t and zero or more vowels use this search: “##[aeiouyt]{0,31}t[aeiouy]{0,31}” Strings of w’s and l’s with at least four w’s in a row can be found with this search: “##[wl]{0,28}w{4}[wl]{0,28}”

Don’t forget to use the dtSearch dictionary for immediate feedback on how well RegEx searches will work.

Remember to use straight quotes. Don’t use curly quotes!


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